This is what I've got so far for the Underwater Contest, It's only 20% complete, and there is much to add.

Features So Far
-Working entrance(The Hydro Shoot)
-Working Story System(In the form of the C.H.A.O.S AI
-Some easter eggs
-Working elevator

Planned
-Large complex
-8 color coded sections(1.5 sections made)
-Make the C.H.A.O.S A.I. make you feel like trash
-Make large glass residential area
-More easter eggs

C.H.A.O.S is based of G.L.A.D.O.S from portal